• 沒有找到結果。

6.1. 結論

我們成功的整合了 AODV 路由協定以及 solicitation-based 的機制,來讓 WAVE network 可以有 ad-hoc mode 的網路存取方式,並且透過最小延遲演算法設計來修改 AODV 程式,實 作出我們所提出的最小延遲多點轉送機制。

理論上透過我們的最小延遲多點轉送機制當資料在傳輸的時候,在路徑搜尋的過程中可以 找到一條延遲時間較小的路徑來傳送資料,所以資料傳輸的延遲時間會比較小。再者,每次都 找延遲時間最小的路徑來傳輸資料,所以抖動率也會比較小比較穩定。而延遲時間小的路徑也 會是頻寬較不壅塞的路徑,因此封包接收率會比較高。而封包接收率比較高的話,吞吐量也會 隨著提高。

最後,我們使用 NS2 模擬軟體來模擬我們所提出的最小延遲多點轉送機制。模擬結果顯 示我們所提出的方法跟現行的 AODV 路由協定相比的話,在平均延遲時間降低了 62.86%、

在封包接收率提高了 19.96%、在平均抖動率改進了 90.62%並且在平均吞吐量提高了 29.59

%。模擬結果和我們所預期的一樣,表示我們所提出的機制可以提高在車載無線網路環境下資 料傳輸的整體效能。

6.2. 未來工作

除了我們提出的最小延遲多點轉送機制之外,未來還可以嘗試最大吞吐量、最大封包接收 率或是最小路徑搜尋頻率等多點轉送機制。因此在未來我們將繼續研究利用車輛與車輛間的多 點轉送機制再結合進階車載網路路由協定以及各種不同的 Routing Metric 來做資料傳輸,找 出最佳的資料存取機制。另外,我們也可以跟不同的路由協定做效能比較,例如:AOMDV、

VADD 和 AODV+等。

而本篇論文我們是將最小延遲多點轉送機制與 AODV 路由協定整合,我們也可以嘗試將 最小延遲多點轉送機制與不同的路由協定做整合,來互相比較效能。

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